1. Field of the Invention
The present invention relates to a network camera for transmitting a photographed image to a client terminal via a network.
2. Description of Related Art
It has been known that there is a technology for viewing an image sent from a network camera installed in a remote place via a network such as the Internet, or a network camera installed within a LAN (Local Area Network), on a screen of a terminal such as a personal computer or a mobile telephone.
A network camera that has a swivel base for swiveling an image sensor unit and is capable of such operations as pan and tilt by a remote operation has been widely available as a common produce in the market. Such a network camera having a swivel base offers great convenience to the user since, for example, it can control the angle of view for taking an image via a net work by swiveling the image sensor unit. It should be noted that such a camera having a swivel base is applied not only to the network camera but also to television systems such as the NTSC (National Television Standards Committee) television system.
In the camera having a swivel base, the swivel base driving unit is usually made up of many components, such as a motor and a speed reduction mechanism (such as gears and belts). These components generally tend to deteriorate more easily than electronic components, and they have predetermined service life. Therefore, periodic maintenance is necessary to use these components sustainably.
With a camera having many wiring cables, all the wiring cables need to be disconnected when removing the camera main unit from the mount base for maintenance, and the workload of the maintenance is considerable. In addition, the network camera having a swivel base is often used for surveillance, so in many cases, the system is not permitted to stop for a long time during maintenance. In particular, in the case where a large number of cameras are used at one location, the wiring cables of all the cameras need to be disconnected during maintenance, and when reinstalling the cameras back to the original locations, wiring needs to be done again. This requires a very large number of work hours.
In view of this, a camera furnished with a one-touch installation mechanism for attaching/detaching a camera main unit and a mount base with a single touch of a button, without cables, has become commonplace in recent years. Network cameras furnished with a one-touch installation mechanism have been widely used, for example, for surveillance.
In the camera furnished with the one-touch installation mechanism, a terminal or the like for connecting to an external device is provided at its mount metal fitting that serves as a base unit, for example, and further wiring cables are connected thereto. Then, the camera is fitted to a wall surface, a ceiling, or the like. The camera main unit is configured so as to be fitted to the mount metal fitting. The camera main unit and the base unit are connected by a connector. In addition, the camera has a mechanical retaining mechanism such as a lock button. The camera furnished with the one-touch installation mechanism with such a configuration can be installed and removed easily. (See, for example, JP-A-2005-26866.)